A household electrical appliance such as an air conditioner or a television is provided with a remote controller, as an accessory, for remotely operating the household electrical appliance. A remote controller generally includes a liquid crystal display (LCD) and a backlight to display a temperature and humidity if the remote controller is for an air conditioner, for example.
In a conventional remote controller, if the temperature and humidity are always displayed, the battery power is wasted and the frequency of battery replacement and charge increases, increasing the work burden on the user.
Given that, a remote controller with a vibration sensor is disclosed (see, for example, Patent Literature 1). In this remote controller, once the vibration sensor detects a vibration caused by a user holding the remote controller in his/her hand, the LCD display is turned on, and then once a predetermined amount of time has passed after the user completes his/her operation, the LCD display is turned off. This reduces power consumed by the remote controller. Since the LCD display is turned on immediately after the vibration sensor detects that a user is holding the remote controller in his/her hand, operability is not impaired.
Meanwhile, a mobile terminal device that can differentiate the vibration caused by a user's running and walking and a dropping of the mobile terminal device is disclosed (see, for example, Patent Literature 2).